The overall objective of this research is to advance our knowledge on the protective sustem of the normal skin and to provide a baseline for studying defects in the pathologic skin. Toward this end proteins of normal and psoriatic horny cells will be studied during the coming grant period. Eponychium, callus and horny cells scraped from the leg are obtained from normal individuals. Psoriatic scales are collected from untreated body regions of patients. The polypeptide composition of soluble proteins and keratin prepared from these horny materials will be studied by PAGE. The relative amount of polypeptides and molecular weight will be determined by spectroscopic method and appropriate markers respectively. Reconstitued filaments will be also prepared and their polypeptide composition compared with that of keratin samples.